Tractors are a common utility vehicle in the farming, construction and landscaping industries. The key benefit of these vehicles is their great versatility. Unlike vehicles dedicated to a specific task, a wide variety of implements and equipment can be attached to and operated by a tractor including loaders, plows, snow throwers, mowers, grappling claws, post hole diggers, forks, bale spears, trenchers, hay balers, cultivators, spreaders and graters, to name a few. In order to efficiently use this wide variety of implements and equipment with a single tractor, however, such implements and equipment must be capable of quick attachment and removal from the tractor, and safe storage when other equipment or implements are being used with the tractor. Accordingly, owners and operators of tractors are constantly seeking new and improved methods and configurations for implements that allow for their quick and safe removal, attachment and storage.
The front end loader is a common implement found on most utility tractors, and its removal, attachment and storage presents specific challenges. The front end loader includes a bucket or scoop that is attached to the end of two lift arms that extend from the front of the tractor, and hydraulic cylinders that connect to the hydraulic system of the tractor to raise and lower the lift arms and rotate the bucket. The front end loader is primarily used to lift, load and transport all types of material including dirt, rocks, feed, sand, gravel, wood and snow. The bucket may also typically be detached from the lift arms so that other implements, such as grappling claws, forks or bale spears, may be attached in place of the bucket and operated by the tractor.
Although useful in many applications, it is often desirable for the operator of a tractor to remove the front end loader from the tractor. When operating an implement or equipment attached to the rear of the tractor, for example, the front end loader may reduce the maneuverability of the vehicle, add unnecessary weight to the vehicle and impair the visibility of the operator. Accordingly, an operator may frequently wish to remove the front end loader from the tractor and, later, reinstall the front end loader on the tractor. Many types of connectors, mechanisms and attachments have been developed to safely, quickly and securely attach a front end loader to a tractor.
A front end loader is typically installed on a heavy duty bracket assembly bolted to and extending up both sides of the tractor. The front end loader includes a tower at the rear end of each lift arm that is attached, near the top, to the lift arm and, lower on the tower, to the lift cylinder. To attach the front end loader to the tractor, the tractor is driven between the lift arms of the front end loader so that the towers at the rear of each lift arm are immediately adjacent to the bracket assembly on each side of the tractor. The hydraulic lines of the front end loader are then connected to the hydraulic system of the tractor. With the hydraulic lines connected, the height and orientation of the towers can be changed by extending and retracting the lift cylinders and implement cylinders of the front end loader. The towers are then engaged with the bracket assembly by manipulating the height and orientation of the towers and/or moving the tractor forward, or some combination of the two. When precisely matched with the bracket assembly, each tower can then be attached and secured to the bracket on both sides of the tractor. The simplicity of the mechanism and the ease with which the tower is aligned with and secured to the bracket assembly largely determines the time necessary for the front end loader to be removed from and, later, reinstalled on the tractor.
A common prior art connection and method for attaching the tower to the bracket assembly is a heavy duty pin that is inserted though the bracket assembly and each tower and secured in place. To utilize this prior art connection, each tower is lowered onto a seat or groove on the bracket assembly. With the lower end of the towers engaged with the bracket assembly, the towers are then rotated backwards and forwards until a hole in each tower perfectly aligns with holes in the bracket assembly. The heavy duty pin is then inserted through the holes to lock the towers into the bracket assembly, and the pin is then locked in place through a variety of means, such as, for example, a cotter pin through the heavy duty locking pin.
Although relatively simple in operation, this connection presents certain challenges and disadvantages. First, it may be difficult to seat the towers in the bracket assembly to begin the process. Second, the holes of the towers and the bracket assembly must be precisely aligned for the pin to slide easily through the holes. Third, the alignment of the holes cannot typically be determined from the operator's seat on the tractor, and the operator must dismount the tractor to determine if the holes are aligned before attempting to insert the pin. Also, the pins cannot typically be inserted from the operator's seat.
If the tractor itself is not aligned perfectly straight between the lift arms, the holes in the towers and the bracket assembly will not properly align. This problem will often not be evident until an operator has placed the tractor between the lift arms, and then attempted to manipulate the position of the towers to align with the brackets, and then dismounted from the driver's seat of the tractor to attempt to insert the pins. When a single operator is attempting to install the front end loader, the operator must often mount and dismount the tractor multiple times, often moving the tractor and the towers in the process, before the pins can be properly aligned. This process takes time, and can be difficult for a novice operator.
In addition, the pins and the holes can become worn over time, leading to a loose connection between the front end loader and the bracket assembly. This loose connection can lead to issues when the loader is operated if the towers are not securely fixed in the bracket assembly. Pins can also be lost or misplaced when the front end loader is stored.
Further, to remove the front end loader from the tractor, an operator must place the implement on the ground and then manipulate the lift and rotation hydraulic cylinders until no force is exerted on the pins by the towers and bracket assembly. If the pin is even only slightly bound to the towers and bracket assembly, an operator must use great strength to remove the pin, or employ a tool to pry the pin from the holes.
Typically, the operator must dismount the tractor to determine if the pins are sufficiently loose for removal. Alternatively, the operator may stand on the side of the tractor and manipulate the front end loader hydraulics until the pin on the side on which the operator standing is loose and can be removed. The pin on the other side of the tractor, however, may still be bound, requiring the operator to run around the tractor, alternatively manipulating the hydraulics and attempting to remove the other pin. Again, this process takes time, and can be difficult for a novice operator.
Thus, although the locking pin mechanism has received widespread use, owners and operators have sought improved configurations and methods for securing a front end loader to a tractor that improve the connection between the loader and the bracket assembly and provide an easier means for a single operator to attach and remove a front end loader without dismounting the tractor.
Accordingly, an object of the present invention is to provide a front end loader configuration and method for attachment and removal that allows the front end loader to be quickly and simply attached and removed from a utility tractor.
A further object of the present invention is to provide a front end loader configuration and method for attachment and removal that does not require the use of tools to attach and remove the front end loader from the tractor, or pins or other attachment devices that can be lost.
Yet another object of the present invention is to provide an attachment device that automatically locks loader arms to a vehicle when the arms are brought into contact with the vehicle.
Finally, an object of the present invention is to provide a front end loader configuration and method for attachment and removal that allows an operator to attach and remove the front end loader without leaving the seat of the tractor, and that allows an operator to determine visually whether the front end loader has been securely connected to the tractor.